Generally, you can access your mobile phone's voicemail from a landline or someone else's phone. How you do this varies between countries and operators. In some cases you can dial your own number and enter a code such as a star (*) or hash (#) and PIN code to access voicemail. In other cases, you must dial an access number depending on the country you are in, then enter your phone number and PIN. You probably cannot access your voicemail from another country unless you have changed your PIN code from the default.  To find more information, try searching your operator's Web site support section under messaging and voicemail.